Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 10 Answered

prove that: sinA-cosA+1/sinA+cosA-1=1/secA-tanA  
Asked by banerjee_milky | 16 Feb, 2019, 11:23: AM
answered-by-expert Expert Answer
For conveneience let us use the substitution, sinA = s and cosA = c
 
begin mathsize 12px style L H S space equals space fraction numerator sin A space minus cos A plus 1 over denominator sin A plus cos A minus 1 end fraction space equals space fraction numerator s minus open parentheses c minus 1 close parentheses over denominator s plus left parenthesis c minus 1 right parenthesis end fraction space

L H S space equals fraction numerator begin display style s minus open parentheses c minus 1 close parentheses end style over denominator begin display style s plus left parenthesis c minus 1 right parenthesis end style end fraction cross times fraction numerator s minus open parentheses c minus 1 close parentheses over denominator s minus open parentheses c minus 1 close parentheses end fraction space equals space fraction numerator begin display style open square brackets s minus open parentheses c minus 1 close parentheses close square brackets squared end style over denominator s squared minus left parenthesis c minus 1 right parenthesis squared end fraction space equals space fraction numerator s squared plus c squared minus 2 c plus 1 minus 2 s c plus 2 s over denominator s squared minus c squared minus 1 plus 2 c end fraction space
l e t space u s space u s e space t h e space i d e n t i t y space s squared plus c squared equals 1 space a n d space s squared minus 1 space equals space minus c squared space space i n space t h e space a b o v e space e x p r e s s i o n
L H S space equals space fraction numerator 2 minus 2 c plus 2 s minus 2 s c over denominator 2 c minus 2 c squared end fraction space equals space fraction numerator open parentheses 1 minus c close parentheses begin display style open parentheses 1 plus s close parentheses end style over denominator c open parentheses 1 minus c close parentheses end fraction space equals space fraction numerator 1 plus s over denominator c end fraction space equals space s e c A plus tan A
end style
begin mathsize 12px style R H S space equals space fraction numerator 1 over denominator s e c A space minus space tan A end fraction space equals space space fraction numerator begin display style 1 end style over denominator begin display style s e c A space minus space tan A end style end fraction cross times fraction numerator s e c A plus tan A over denominator s e c A plus tan A end fraction space equals space fraction numerator s e c A space plus space tan A over denominator s e c squared A space minus space tan squared A end fraction space equals space s e c A space plus space tan A space open square brackets because space s e c squared A space minus space tan squared A space equals space 1 space close square brackets end style
hence we have proved LHS = RHS,
Answered by Thiyagarajan K | 16 Feb, 2019, 12:44: PM
CBSE 10 - Maths
Asked by dheerrana109 | 22 Jul, 2024, 10:26: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by ishakkumbhar92 | 20 Jul, 2024, 16:09: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by vishwanathhikkalagutti | 17 Jul, 2024, 07:25: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by avadheshkumar94 | 13 Jul, 2024, 20:18: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by 3ra2231 | 11 Jul, 2024, 20:55: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by avadheshkumar94 | 10 Jul, 2024, 10:14: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by syashkurun | 08 Jul, 2024, 19:14: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by francissaka528 | 08 Jul, 2024, 06:15: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by radhe9868017031 | 05 Jul, 2024, 14:10: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by naidulokesh892 | 04 Jul, 2024, 20:42: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
Are You a Teacher or a Parent Seeking Customised Tests? Click here
×